BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is a treatment option for peritoneal surface malignancies. The ability to detect microscopic foci of peritoneal metastasis intraoperatively may ensure the completeness of cytoreduction. In this study, we evaluated the suitability of a hand-held cathepsin-based fluorescent imaging system for intraoperative detection of appendiceal and colorectal peritoneal metastasis. METHODS: Peritoneal tumors and normal peritoneal tissues were collected from patients with appendiceal and colorectal peritoneal metastasis...

Endometriosis of the appendix can be an incidental finding or a cause of appendicitis, intussusception, perforation or retention mucocele. Intestinal metaplasia of appendiceal endometriosis may occur, which can lead to a misdiagnosis of low-grade appendiceal mucinous neoplasm. On a retrospective search of the pathology database from 2001 to 2015, we identified 78 appendiceal endometriosis cases and intestinal metaplasia was present in 10/78 (13%) cases. In most of the cases (90%), the foci of intestinal metaplasia were mainly localized close to the mucosa...

Primary appendiceal mucinous lesions are uncommon and represent a spectrum from nonneoplastic mucous retention cysts to invasive adenocarcinoma. Low-grade appendiceal mucinous neoplasms (LAMNs) represent an intermediate category on this spectrum and can be classified according to whether or not they are confined to the appendix. Although LAMNs are frequently confined to the appendix, they can also spread to the peritoneum and clinically progress as pseudomyxoma peritonei (i.e., mucinous ascites). Thus, the appropriate classification of appendiceal primary neoplasia is essential for prognosis and influences clinical management...

BACKGROUND: Mucinous appendiceal neoplasms (MAN) with peritoneal dissemination is treated as a standard of care using cytoreductive surgery and hyperthermic perioperative chemotherapy. The extent of the resection of peritoneal surfaces and visceral structures is generally well defined. Exception to this consensus regarding structures to be removed are the right colon and adjacent ileocolic lymph nodes. METHODS: From a prospectively maintained database, all patients with a histologic diagnosis of peritoneal mucinous carcinoma (PMCA) who underwent complete cytoreductive surgery were assessed for the presence versus absence of adenocarcinoma in lymph nodes within the appendiceal mesentery and/or in the lymph nodes of the ileocolic group...

BACKGROUND: There is little evidence for the use of early postoperative intraperitoneal chemotherapy (EPIC) in patients with low-grade appendiceal mucinous neoplasms (LAMNs) with pseudomyxoma peritonei (PMP). This study aims to assess the outcomes regarding the use of EPIC in a large cohort of patients with LAMNs with PMP uniformly treated by cytoreductive surgery (CRS) and perioperative intraperitoneal chemotherapy (PIC), all of whom received hyperthermic intraperitoneal chemotherapy (HIPEC), and most of whom also received EPIC...

Heterotopic ossification occurring to low-grade appendiceal mucinous neoplasm (LAMN) (pseudomyxoma peritonei) is extremely rare. The pathogenetic mechanism of the tumor-related heterotopic bone formation remains as yet unconfirmed. Here, we describe a rare case of LAMN with ossification in a 72-year-old woman, and concentrate on the etiology of heterotopic ossification by the immunohistochemical evaluation of the novel markers such as BMP9, osteocalcin, and osteopontin. BMP9 is one of the most effective osteogenetic proteins...

Low-grade appendiceal mucinous neoplasm is a neoplasm typically of appendiceal origin, which is characterized by diffuse peritoneal involvement by pools of mucin with mucinous epithelium lacking high-grade cytologic atypia, and clinically presents as suspected peritoneal carcinomatosis. A similar clinical presentation can sometimes be seen with disseminated low-grade serous carcinomas of the peritoneum, fallopian tubes, or ovaries; however, this neoplasm is histologically characterized by tubal-type epithelium and invasive or confluent growth...

BACKGROUND: Low-grade appendiceal mucinous neoplasm of uncertain malignant potential are poorly understood lesions characterized by extraluminal mucin or fibrosis with neoplastic cells confined to the appendiceal lumen. The purpose of this study is to investigate the clinical and pathologic parameters of these lesions to optimize our understanding and management of these tumors. METHODS: Subjects with these tumors were identified from the appendiceal tumor databases at the University of Texas MD Anderson Cancer Center...

INTRODUCTION: The prognosis of appendiceal mucinous neoplasms (AMN) is directly related to their histopathology. Existing classification schemes encompass tumors with widely divergent clinical behaviors within a single diagnosis, making it difficult for clinicians to interpret pathology reports to counsel patients on optimal management. We sought to examine pathology reports generated for AMN for inclusion of essential histologic features. METHODS: Pathology reports of appendectomy specimens with a diagnosis of AMN (2002-2015) at our center ("internal") and from referring institutions ("external") were retrospectively reviewed for inclusion of the following 5 essential items: layer of invasion, mucin dissection (low grade neoplasms only), perforation, margins, and serosal implants...

BACKGROUND: Disseminated peritoneal adenomucinosis (DPAM) patients often have a history of appendectomy with identification of an incidental mucinous neoplasm (low-grade appendiceal mucinous neoplasm (LAMN)). The rate of developing DPAM is not well established. METHODS: Twenty-two patients with incidental LAMN were identified and monitored with cancer markers and CT every 4-6 months. Laparoscopy with peritoneal washing was performed in patients either in the event of radiographic disease or after 12 months in absence of radiographic disease...

Pseudomyxoma retroperitonei is a rare condition, characterized by accumulation of mucinous material in the retroperitoneal space, originating predominantly from the appendiceal mucinous neoplasms. A72-year-old male patient presented with a history of progressive right side abdominal pain for 5 months with a palpable abdominal mass. Ultrasound, computerized tomography, and magnetic resonance imaging showed large right abdominal multiloculated cystic lesion with heterogeneous echoic contents. Colonoscopy revealed normal mucosa with extramural pressure on the right colon and cecum...

Mucinous neoplasms of the urinary tract are very rare. We present a 63-year-old-women who had a sessile papillary villous tumor in urinary bladder. Although transurethral resection of the bladder tumor (TURBT) was performed, the villous tumor repetitively recurred and gradually spread to the entire surface of bladder lumen. Histopathologic and immunohistochemical examination showed that the lesion was very similar to low-grade mucinous neoplasm arising in appendix vermiformis. There are no reports on appendiceal metaplasia of urinary bladder mucosa...

Heterotopic bone formation is a very rare event in the gastrointestinal tract including in the appendix. Here we report three cases of heterotopic ossification in appendiceal mucinous neoplasms, one occurring in an appendiceal mucinous cystadenoma, another in a low-grade appendiceal mucinous neoplasm, and the third occurring in an appendiceal mucinous adenocarcinoma. The clinicopathologic characteristics of these three present cases and two previously reported cases are discussed in detail. The mechanism of heterotopic ossification in appendiceal mucinous neoplasm is still unclear, but mucin extravasation and subsequent calcification may be predisposing events...

Appendiceal mucocele is a rare cause of acute abdomen. Mucinous appendiceal neoplasms represent 0.2-0.7% of all appendix specimens. The aim of this study is to report a case of a mucinous appendiceal neoplasm presented as acute appendicitis, discussing the clinical and surgical approach in the emergency setting. A 72-year-old female patient was admitted to the emergency department with a clinical examination indicative of acute abdomen. The patient underwent abdominal computed tomography scan which revealed a cystic lesion in the right iliac fossa measuring 8...

Neoplasms of the appendix are rare, but because of their unusual presentation and unpredictable biologic behavior, it is important to diagnose them correctly. Mucinous tumors account for 58 % of malignant tumors of appendix in SEER database and the remaining are carcinoids. The mucinous appendiceal tumors have a potential to spread to the peritoneum and viscera in the form of gelatinous material with or without neoplastic cells resulting in Pseudomyxoma peritonei. (PMP) PMP is a clinical entity that has a unique biological behavior and can arise from seemingly benign tumors to frankly malignant ones...

BACKGROUND: Mucinous cystadenocarcinoma is the second most common etiology of appendiceal mucocele. We report a relatively rare case of a giant appendiceal mucocele caused by mucinous cystadenocarcinoma, which occupied the entire abdomen of an adult woman. CASE PRESENTATION: A 63-year-old woman presented with a chief complaint of abdominal distention. Imaging studies showed a giant cystic mass occupying her entire abdomen. Laparotomy confirmed a giant appendiceal mucocele, and the patient underwent ileocecal resection...

Mucinous appendiceal neoplasm occurs in less than 1% of appendicectomies. Majority of what is known in the literature is about pseudomyxoma peritonei, which exists as its disseminated form. Pictorial imagery of its pre-disseminated form is rarely observed. We present in a case report form a case of low-grade mucinous neoplasm of the appendix resulting in focal intussusception including images captured from this unique case that will become a learning case for readers of the journal.

BACKGROUND: The importance of absent neoplastic epithelium in specimens from cytoreductive surgery (CRS) is unknown. This study aimed to investigate the prevalence and prognostic value of histopathology without neoplastic epithelium in patients treated with CRS and hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: Data were extracted from medical records and histopathology reports for patients treated with initial CRS and HIPEC at Uppsala University Hospital, Sweden, between 2004 and 2012...

The primary origin of some ovarian mucinous tumors may be challenging to determine, because some metastases of extraovarian origin may exhibit gross, microscopic, and immunohistochemical features that are shared by some primary ovarian mucinous tumors. Metastases of primary colorectal, appendiceal, gastric, pancreatic, and endocervical adenocarcinomas may simulate primary ovarian mucinous cystadenoma, mucinous borderline tumor, or mucinous adenocarcinoma. Recently, immunohistochemical expression of SATB2, a transcriptional regulator involved in osteoblastic and neuronal differentiation, has been shown to be a highly sensitive marker of normal colorectal epithelium and of colorectal adenocarcinoma...